Sampling Device to Extract Inclined, Undisturbed Soil Cores

Abstract

Abstract

A sampling device was constructed to extract undisturbed cores of soil or similar material at angles between 0 and 90° from the vertical. The sampler consisted of a hydraulic cylinder suspended from an arm of a backhoe. Undisturbed cores (76-mm in ht. by 76-mm in diam.) were collected in metal rings, which were inserted into a Uhland-type sample holder. The hydraulic cylinder pushed the sample holder into the soil material and also extracted it. Twenty-five undisturbed, inclined cores could be collected with this device in 3 hr by three people. Saturated hydraulic conductivity was measured on 120 saprolite cores using a double-ring permeameter to assess boundary flow. No boundary flow was detected between the sample ring and core edge. Examination of the cores' internal fabric, as seen in thin sections made from each of the 120 cores, confirmed that the cores were virtually undisturbed.